change &rtp manipulation
change &rtp manipulation

- make it append only (instead both append + prepend)
- which draws *_rm_a and *_add_a useless as &rtp order gets preserved
- benefits: simpler, faster, less code

sensorario/Vundle.vim,akiniwa/dotfiles,kotamat/vundle,kotamat/vundle,ppslinux/Vundle.vim,kotamat/vundle,akiniwa/dotfiles,akiniwa/dotfiles,akiniwa/dotfiles,omalsa04/dotfiles,stephaneliu/dotfiles,kotamat/vundle,TLmaK0/my_vim_config,ppslinux/Vundle.vim,ppslinux/Vundle.vim,stephaneliu/dotfiles,kotamat/vundle,ppslinux/Vundle.vim,omalsa04/dotfiles,akiniwa/dotfiles,ppslinux/Vundle.vim,akiniwa/dotfiles,ppslinux/Vundle.vim